The invention relates to a method, an arrangement and the use of an arrangement for separating metallic carbon nanotubes from semi-conducting carbon nanotubes.
Macro-molecules in which carbon atoms form the outside wall of a tube are called carbon nanotubes. For the prototype, a single-wall carbon nanotube is described with the aid of a planar ribbon of hexagonally arranged carbon atoms, which is rolled up seamlessly to form a tube. Several concentric tubes, arranged one inside the other, are referred to as multi-wall carbon nanotubes.
Typical single-wall carbon nanotubes have a diameter of 0.5 nm to 10 nm while multi-wall carbon nanotubes have a correspondingly larger diameter. Typical carbon nanotubes ranges in length from 100 nm to a few 10 micrometers, wherein the carbon nanotubes can be cut into smaller sections as well as extended by fitting them together for some methods.
Carbon nanotubes are divided into two categories because of their electronic characteristics: metallic carbon nanotubes and semi-conducting carbon nanotubes. Metallic carbon nanotubes are suitable for use as molecular wires with extremely high current-carrying capacity which are resistant to electro-migration. Semi-conducting carbon nanotubes are particularly suitable as molecular transistors. Both types represent promising components for nano-electronic circuits because of their nanoscale dimensions.
It is absolutely necessary for the production of nanoscale circuits from carbon nanotubes that metallic and semi-conducting carbon nanotubes can be manipulated separately, thus requiring metallic carbon nanotubes or semi-conducting carbon nanotubes to be produced as type-specific as possible and/or to separate these.